Minutes, IBIS Quality Committee 07 Oct 2008 11-12 AM EST (8-9 AM PST) ROLL CALL Adam Tambone Anders Ekholm, Ericsson Barry Katz, SiSoft Benny Lazer Benjamin P Silva Bob Cox, Micron * Bob Ross, Teraspeed Consulting Group Brian Arsenault * David Banas, Xilinx * Eckhard Lenski, Nokia Siemens Networks Eric Brock * Guan Tao, Huawei Technologies Gregory R Edlund Hazem Hegazy Huang Chunxing, Huawei Technologies John Figueroa John Angulo, Mentor Graphics Katja Koller, Nokia Siemens Networks Kevin Fisher Kim Helliwell, LSI Logic Lance Wang, IOMethodology Lynne Green * Mike LaBonte, Cisco Systems Mike Mayer, SiSoft * Moshiul Haque, Micron Technology * Pavani Jella, TI Peter LaFlamme Randy Wolff, Micron Technology Radovan Vuletic, Qimonda Robert Haller, Enterasys Roy Leventhal, Leventhal Design & Communications Sherif Hammad, Mentor Graphics Todd Westerhoff, SiSoft Tom Dagostino, Teraspeed Consulting Group Kazuyoshi Shoji, Hitachi Sadahiro Nonoyama Everyone in attendance marked by * NOTE: "AR" = Action Required. -----------------------MINUTES --------------------------- Mike LaBonte conducted the meeting. Call for patent disclosure: - No one declared a patent. AR Review: - Mike post IQ spec 1.1ai draft - Done New items: Continued review of the IBIS Quality Specification: - Mike: The 1.1ai draft IQ spec as posted may not have revision note for changes that were made to 5.5.1 5.5.2. {LEVEL 2} [Ramp] R_load present if value other than 50 ohms - IBISCHK can't check for this - Mike: It would have been better if R_load were always required - Bob: IBIS did not have R_load initially - Is this level a 2 check? - Mike: what goes wrong if R_load is wrong? - It is possible to check [Ramp] against equivalent waveforms - Bob: Would ODT be checked? - Mike: R_load affects neither waveforms nor timing - But not all models have waveforms - We agreed to leave this check unchanged 5.5.3. {LEVEL 2} [Ramp] test fixture has no reactives - Mike: Sometimes we see IBIS files with [Ramp] not matching waveforms - Sometimes min/max V are taken from peaks, not endpoints - Some buffers have a reverse bump before the real edge begins - Maybe sometimes reactive fixtures are used - Bob: There was some discussion in the past about adding more [Ramp] params - Moshiul: If the model is made from measurement this is unavoidable - Bob: The fixture RLC can be de-embedded when the model is made - Moshiul: What do we recommend for waveforms with regard to reactives? - The IQ spec has no mention of prohibiting reactives in the waveform checks - 5.5.7 makes an allowance for waveform reactives - Should we allow reactives? - Guan: It should be OK, but Ramp and waves should have same fixture. - David: Why are reactives a problem? - Mike: An R-only fixture waveform is needed for simulators to calc K factor - If there are reactives they have to be de-embedded - Bob: We had to allow for reactive fixtures when this was created. - I-V and V-T tables have to be smooth to avoid abrupt K changes - David: Are we moving away from bench measured models? - Mike: There is pressure to avoid those because min/max is not present - There may be some models that have the package de-embedded - Moshiul: Are simulator algorithms dealing with the problem? - Bob: Some simulators may even ignore reactives - Mike: If L & C are de-embedded from the model the [LC]_fixtures are absent - Simulators should simulate it the same way - Moshiul: The IBIS spec discourages reactives - Mike: Then IQ should be able to ban them - Mike: Should we have a new 5.4 check banning reactives in waveforms? - We will discuss this next week Next meeting: 14 Oct 2008 11-12 AM EST (8-9 AM PST) Meeting ended at 12:07 PM Eastern Time.